Coastal Single-beam Bathymetry Data Collected in 2022 off Seven Mile Island, New Jersey

Frequently anticipated questions:

• What does this data set describe?
  1. How might this data set be cited?
  2. What geographic area does the data set cover?
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
  5. What is the general form of this data set?
  6. How does the data set represent geographic features?
  7. How does the data set describe geographic features?
• Who produced the data set?
  1. Who are the originators of the data set?
  2. Who also contributed to the data set?
  3. To whom should users address questions about the data?
• Why was the data set created?
• How was the data set created?
  1. From what previous works were the data drawn?
  2. How were the data generated, processed, and modified?
  3. What similar or related data should the user be aware of?
• How reliable are the data; what problems remain in the data set?
  1. How well have the observations been checked?
  2. How accurate are the geographic locations?
  3. How accurate are the heights or depths?
  4. Where are the gaps in the data? What is missing?
  5. How consistent are the relationships among the data, including topology?
• How can someone get a copy of the data set?
  1. Are there legal restrictions on access or use of the data?
  2. Who distributes the data?
  3. What's the catalog number I need to order this data set?
  4. What legal disclaimers am I supposed to read?
  5. How can I download or order the data?
• Who wrote the metadata?

What does this data set describe?

1. How might this data set be cited?
   DeWitt, Nancy T., and Lyons, Erin O., 20231101, Coastal Single-beam Bathymetry Data Collected in 2022 off Seven Mile Island, New Jersey:.

   This is part of the following larger work.
   Lyons, Erin O., DeWitt, Nancy T., Stalk, Chelsea A., Reynolds, Billy J., Farmer, Andrew S., Bernier, Julie C., Galbraith, Benjamin A., Wei, Emily A., and Miselis, Jennifer L., 20231101, Coastal Single-beam Bathymetry Data Collected in 2022 off Seven Mile Island, New Jersey: U.S. Geological Survey data release doi:10.5066/P9P07T3W, U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center, St. Petersburg, Florida.

   Online Links:

   • https://doi.org/10.5066/P9P07T3W

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -74.786191
   East_Bounding_Coordinate: -74.684937
   North_Bounding_Coordinate: 39.106510
   South_Bounding_Coordinate: 39.008541
   

3. What does it look like?
4. Does the data set describe conditions during a particular time period?

   Beginning_Date: 29-Apr-2022

   Ending_Date: 02-May-2022

   Currentness_Reference:

   ground condition

5. What is the general form of this data set?

   Geospatial_Data_Presentation_Form: tabular and vector digital data
   

6. How does the data set represent geographic features?
   1. How are geographic features stored in the data set?
      This is a Point data set. It contains the following vector data types (SDTS terminology):
      • Point (1,627,024)
   2. What coordinate system is used to represent geographic features?
      

      Grid_Coordinate_System_Name: Universal Transverse Mercator
      Universal_Transverse_Mercator:

      UTM_Zone_Number: 18N
      Transverse_Mercator:

      Scale_Factor_at_Central_Meridian: 0.999600
      Longitude_of_Central_Meridian: -75.000000
      Latitude_of_Projection_Origin: 0.000000
      False_Easting: 500000.000000
      False_Northing: 0.000000
      

      Planar coordinates are encoded using coordinate pair
      Abscissae (x-coordinates) are specified to the nearest 0.6096
      Ordinates (y-coordinates) are specified to the nearest 0.6096
      Planar coordinates are specified in meters
      The horizontal datum used is World Geodetic System of 1984.
      The ellipsoid used is WGS_1984.
      The semi-major axis of the ellipsoid used is 6378137.000000.
      The flattening of the ellipsoid used is 1/298.257223563.
      

      Vertical_Coordinate_System_Definition:

      Altitude_System_Definition:

      Altitude_Datum_Name: North American Vertical Datum 1988
      Altitude_Resolution: 0.01
      Altitude_Distance_Units: meters
      Altitude_Encoding_Method: Attribute values
      

7. How does the data set describe geographic features?

   Seven_Mile_Island_2022_SBES_WGS84_UTM18N_xyz.txt

   Comma-delimited ASCII text file (.txt) containing the processed single-beam bathymetry data points from USGS FAN 2022-309-FA (subFANs 22BIM03 and 22BIM05). Data are in the native acquisition and processing datum WGS84 (G2139) UTM Zone 18N. Text file attributes include easting, northing (WGS84 G2139 UTM 18N), ellipsoid height (WGS84 G2139 UTM 18N), latitude (WGS84 G2139 UTM 18N), longitude (WGS84 G2139 UTM 18N), year, day of year (DOY), UTC time, and trackline name. (Source: U.S. Geological Survey)

   WGS84_UTM18N_X

   x-axis coordinate, easting, WGS84 UTM 18N. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	518511.843
   Maximum:	527241.059
   Units:	meters

   WGS84_UTM18N_Y

   y-axis coordinate, northing, WGS84 UTM 18N. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	4317771.501
   Maximum:	4328618.007
   Units:	meters

   WGS84_ELLIPSOID

   z-value, ellipsoid height (elevation), WGS84 UTM18N. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	-51.138
   Maximum:	-36.737
   Units:	meters

   WGS84_UTM18N _LAT

   x-axis coordinate, latitude, WGS84. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	39.008728
   Maximum:	39.106332
   Units:	Decimal Degrees

   WGS84_UTM18N_LONG

   y-axis coordinate, longitude, WGS84. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	-74.786156
   Maximum:	-74.684979
   Units:	Decimal Degrees

   YEAR

   Calendar year of data acquisition. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	2022
   Maximum:	2022

   DOY

   Day of Year of data acquisition. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	119
   Maximum:	122

   UTC_TIME

   UTC time of data acquisition. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	13:21:09.516
   Maximum:	21:13:06.487
   Units:	HH:MM:SS.sss

   HYPACK_LINE

   Identifier assigned to each HYPACK line during acquisition. (Source: HYPACK/U.S. Geological Survey) Example: 22BIM03_SLED_0002_1741_1000, where the first 8 characters are the subFAN followed by an underscore (22BIM03_ or 22BIM05_), the next 5 characters are the platform/vessel followed by and underscore (SLED_ or WVR2_), the next 14 characters are the HYPACK Line number and start time in UTC (0002_1741). If the line number has a segment there will be a value amended to that line (_1000, _2000, etcetera).

   Seven_Mile_Island_2022_SBES_NAD83_NAVD88_UTM18N_GEOID18_xyz.txt

   Comma-delimited ASCII text file (.txt) containing of the processed single-beam bathymetry data points from USGS FAN 2022-309-FA (subFANs 22BIM03 and 22BIM05). Data were re-projected from its native datum to NAD83 NAVD88 UTM Zone 18 North coordinate system with respect to the GEOID 18 datum. Text file attributes include easting (NAD83 UTM 18N), northing (NAD83 UTM 18N), orthometric height (NAVD88 GEOID 18), latitude (NAD83 UTM 18N), longitude (NAD83 UTM 18N), year, day of year (DOY), UTC time, trackline name. (Source: VDatum)

   NAD83_UTM18N_X

   x-axis coordinate, easting, NAD83 UTM 18N. (Source: VDatum)

   Range of values
   Minimum:	518512.3965
   Maximum:	527241.6115
   Units:	meters

   NAD83_UTM18N_Y

   y-axis coordinate, northing, NAD83 UTM 18N. (Source: VDatum)

   Range of values
   Minimum:	4317770.4796
   Maximum:	4328616.9829
   Units:	meters

   NAVD88_G18

   z-value, orthometric height (elevation) in NAVD88 GEOID 18 (Source: VDatum)

   Range of values
   Minimum:	-14.401
   Maximum:	-0.051
   Units:	meters

   NAD83_UTM18N_LAT

   x-axis coordinate, latitude, NAD83 UTM 18N. (Source: VDatum)

   Range of values
   Minimum:	39.021005483
   Maximum:	39.022864782
   Units:	Decimal Degrees

   NAD83_UTM18N_LONG

   y-axis coordinate, longitude, NAD83 UTM 18N. (Source: VDatum)

   Range of values
   Minimum:	-74.781414435
   Maximum:	-74.779292437
   Units:	Decimal Degrees

   YEAR

   Calendar year of data acquisition. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	2022
   Maximum:	2022

   DOY

   Day of Year of data acquisition. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	119
   Maximum:	122

   UTC_TIME

   UTC time of data acquisition. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	13:21:09.516
   Maximum:	21:13:06.487
   Units:	HH:MM:SS.sss

   HYPACK_LINE

   Identifier assigned to each HYPACK line during acquisition. (Source: HYPACK/U.S. Geological Survey) Example: 22BIM03_SLED_0002_1741_1000, where the first 8 characters are the subFAN followed by an underscore (22BIM03_ or 22BIM05_), the next 5 characters are the platform/vessel followed by and underscore (SLED_ or WVR2_), the next 14 characters are the HYPACK Line number and start time in UTC (0002_1741). If the line number has a segment there will be a value amended to that line (_1000, _2000, etcetera).

   Seven_Mile_Island_2022_SBES_NAD83_NAVD88_UTM18N_GEOID12B_xyz.txt

   Comma-delimited ASCII text file (.txt) containing of the processed single-beam bathymetry datapoints from USGS FAN 2022-309-FA (subFANs 22BIM03 and 22BIM05). Data were re-projected from its native datum to NAD83 NAVD88 UTM Zone 18 North coordinate system with respect to the GEOID 12B datum. Text file attributes include easting (NAD83 UTM 18N), northing (NAD83 UTM 18N), orthometric height (NAVD88 GEOID 12B), latitude (NAD83 UTM 18N), longitude (NAD83 UTM 18N), year, day of year (DOY), UTC time, trackline name. (Source: VDatum)

   NAD83_UTM18N_X

   x-axis coordinate, easting, NAD83 UTM 18N. (Source: VDatum)

   Range of values
   Minimum:	518512.3931
   Maximum:	527241.6081
   Units:	meters

   NAD83_UTM18N_Y

   y-axis coordinate, northing, NAD83 UTM 18N. (Source: VDatum)

   Range of values
   Minimum:	4317770.4808
   Maximum:	4328616.9841
   Units:	meters

   NAVD88_G12B

   z-value, orthometric height (elevation) in NAVD88 GEOID 12B. (Source: VDatum)

   Range of values
   Minimum:	-14.401
   Maximum:	-0.051
   Units:	meters

   NAD83_UTM18N_LAT

   x-axis coordinate, latitude, NAD83 UTM 18N. (Source: VDatum)

   Range of values
   Minimum:	39.021005482
   Maximum:	39.022864782
   Units:	Decimal Degrees

   NAD83_UTM18N_LONG

   y-axis coordinate, longitude, NAD83 UTM 18N. (Source: VDatum)

   Range of values
   Minimum:	-74.781414435
   Maximum:	-74.779292437
   Units:	Decimal Degrees

   YEAR

   Calendar year of data acquisition. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	2022
   Maximum:	2022

   DOY

   Day of Year of data acquisition. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	119
   Maximum:	122

   UTC_TIME

   UTC time of data acquisition. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	13:21:09.516
   Maximum:	21:13:06.487
   Units:	HH:MM:SS.sss

   HYPACK_LINE

   Identifier assigned to each HYPACK line during acquisition. (Source: HYPACK/U.S. Geological Survey) Example: 22BIM03_SLED_0002_1741_1000, where the first 8 characters are the subFAN followed by an underscore (22BIM03_ or 22BIM05_), the next 5 characters are the platform/vessel followed by and underscore (SLED_ or WVR2_), the next 14 characters are the HYPACK Line number and start time in UTC (0002_1741). If the line number has a segment there will be a value amended to that line (_1000, _2000, etcetera).

   Seven_Mile_Island_2022_SBES_WGS84_UTM18N_tracklines.shp

   Polyline shapefile of the single-beam bathymetry tracklines containing FID, Shape, HYPACK Line name, and line length (in meters). (Source: Esri)

   FID

   Automatically generated feature attribute by Esri. (Source: Esri)

   Range of values
   Minimum:	0
   Maximum:	348

   Shape*

   Automatically generated feature attribute by Esri. (Source: Esri) PolylineZM

   Length_m

   Length of the trackline polyline, in meters. (Source: Esri)

   Range of values
   Minimum:	0.107798
   Maximum:	13608.518389
   Units:	meters

   HYPACK_LINE

   Identifier assigned to each HYPACK line during acquisition. (Source: HYPACK/U.S. Geological Survey) Example: 22BIM03_SLED_0002_1741_1000, where the first 8 characters are the subFAN followed by an underscore (22BIM03_ or 22BIM05_), the next 5 characters are the platform/vessel followed by and underscore (SLED_ or WVR2_), the next 14 characters are the HYPACK Line number and start time in UTC (0002_1741). If the line number has a segment there will be a value amended to that line (_1000, _2000, etcetera).

Who produced the data set?

1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
   • Nancy T. DeWitt
   • Erin O. Lyons
2. Who also contributed to the data set?
   Funding and (or) support for this study were provided by the National Fish and Wildlife Foundation (NFWF) Beach and Marsh Monitoring Project and the USGS Coastal and Marine Hazards and Resources Program, specifically the Costal Sediment Availability and Flux (CSAF) project.
3. To whom should users address questions about the data?
   Erin O. Lyons

   Cherokee Nation System Solutions

   Biological Scientist Researcher V

   600 4th Street South

   St. Petersburg, FL
   

   USA

   727-502-8000 (voice)

   elyons@contractor.usgs.gov

Why was the data set created?

How was the data set created?

1. From what previous works were the data drawn?
2. How were the data generated, processed, and modified?

   Date: 2022 (process 1 of 6)

   GNSS Acquisition: Two Global Navigational Satellite Systems (GNSS) base stations were established on NGS benchmarks in which the roving vessels would be within 12-15 kilometers (km) of the base station at a given time. The primary benchmark JU04 (PID: JU0450) was located approximately in the middle of the survey extent where the secondary base station DP15 (PID: DP1533) was located to the northeast. The base stations were continually occupied and equipped with a Spectra Precision SP90M GNSS receiver recording full-carrier-phase positioning signals from satellites via Trimble Zephyr 3 Base GNSS antennas recording at a rate of 0.1 second (s). Person who carried out this activity:
   

   Erin O. Lyons

   Cherokee Nation System Solutions

   Biological Scientist Researcher V

   600 4th Street South

   St. Petersburg, FL
   

   USA

   727-502-8000 (voice)

   elyons@contractor.usgs.gov

   Date: 2022 (process 2 of 6)

   Single-Beam Bathymetry Acquisition: The single-beam bathymetric data collected under the USGS Field Activity Number (FAN) 2022-309-FA, include two separate survey platforms; a floating seismic-sled towed by the R/V Sallenger (SLED - subFAN 22BIM03), and the R/V CHUM (WVR2 - subFAN 22BIM05), a 12-ft (foot) Yamaha PWC. The SLED collected 135.48 line-km (288 lines) and the WVR2 collected 145.46 line-km (60 lines). Boat motion was recorded at 50-millisecond (ms) using a SBG Ellipse A motion sensor. HYPACK A Xylem Brand (version 21.0.2.0), a marine surveying, positioning, and navigation software package, managed the planned-transect information and provided real-time navigation, steering, correction, data quality, and instrumentation-status to the boat operator. Depth soundings were recorded at 50-ms intervals using an Odom echotrac CV100 echosounder with a 4-degree, 200-kilohertz (kHz) transducer. Data from the GNSS receiver, motion sensor, and echosounder were recorded in real-time aboard all vessels independently and merged into a single raw data file (.RAW) in HYPACK, with each device string referenced by a device identification code and time stamped to Coordinated Universal Time (UTC). Sound velocity profile (SVP) measurements were collected using SonTek Castaway Conductivity, Temperature, and Depth (CTD) instruments. The instruments were periodically cast overboard to record changes in water column speed of sound (SOS). A total of 202 successful sound velocity casts were collected and ranged in depth from 0.15 to 3.26 m, and in sound velocity from 1490.30 to 1490.59 meters per second (m/s). Person who carried out this activity:
   

   Erin O. Lyons

   Cherokee Nation System Solutions

   Biological Scientist Researcher V

   600 4th Street South

   St. Petersburg, FL
   

   USA

   727-502-8000 (voice)

   elyons@contractor.usgs.gov

   Date: 2023 (process 3 of 6)

   Differentially Corrected Navigation Processing: The NGS horizontal published numbers for Permanent Identifier (PID) JU0450, stamping STONE HARBOR 1932, was retrieved from the NGS datasheet database and converted from NAD83 (2011) UTM 18N into WGS84 (G2139) using the HTDP online transformation utility version 3.5.0 (https://www.ngs.noaa.gov/TOOLS/Htdp/Htdp.shtml). The resultant base position used for post-processing was 39°02’21.66695 North (WGS84-G2139), 74°46’08.81537 West (WGS84-G2139), and -34.526 meters (m) ellipsoid height (WGS84-G2139). The kinematic trajectories (rover to base) and base station coordinates were imported and processed using NovAtel’s Waypoint GrafNav software. Each kinematic GNSS data session from the survey vessel was post-processed to the concurrent base GNSS data session. Analyzing the data plots, trajectory maps, processing logs, satellite health plots, and other viewing utilities that GrafNav produces, provided measures to attain trajectory solutions (between the base and the rover) free of erroneous data that resulted in fixed positions. Some examples include 1) excluding satellites flagged by the program as having bad/poor health or cycle slips, 2) Excluding poor satellite time segments that have a negative influence toward a fixed solution, and 3) adjusting the satellite elevation mask angle to improve the position solutions. The final differentially corrected, precise DGPS positions were computed at 0.1 s and exported in American Standard Code for Information Interchange (ASCII) text format in WGS84 (G2139) UTM 18N geodetic datum. Person who carried out this activity:
   

   Erin O. Lyons

   Cherokee Nation System Solutions

   Biological Scientist Researcher V

   600 4th Street South

   St. Petersburg, FL
   

   USA

   727-502-8000 (voice)

   elyons@contractor.usgs.gov

   Date: 2023 (process 4 of 6)

   Bathymetry Processing: All data were processed using CARIS HIPS and SIPS (Hydrographic Information Processing System and Sonar Information Processing System) version 11.4.23. First, a vessel file *.vhf unique to the platform, was created that contains the surveyed offsets measurements between the sensors. A CARIS project was created using the *.vhf file, and then the HYPACK .RAW and the SPV profiles *.SVP were loaded. Next, the differentially corrected navigation files were imported using the generic data parser tool. Then, the differently corrected navigation files overwrote every non-differential position in the HYPACK .RAW file based upon time. The bathymetric data components (position, motion, depth, and SOS) were then georeferenced and geometrically corrected in CARIS to produce processed x,y,z positional data. Once georeferenced, the data were reviewed and edited for outliers, including further review in the Subset Editor utility for crossing status, and questionable areas or data points were removed. The geometrically corrected point data were then exported as an x,y,z ASCII text file referenced to WGS84 (G2139) UTM 18N. Person who carried out this activity:
   

   Erin O. Lyons

   Cherokee Nation System Solutions

   Biological Scientist Researcher V

   600 4th Street South

   St. Petersburg, FL
   

   USA

   727-502-8000 (voice)

   elyons@contractor.usgs.gov

   Data sources produced in this process:

   • 22BIM03_SLED_SBES_WGS84_UTM18N_Level003_xyz.txt
   • 22BIM05_WVR2_SBES_WGS84_UTM18N_Level003_xyz.txt

   Date: 2023 (process 5 of 6)

   Quality Control, Quality Assurance (QA/QC) and Uncertainty Analysis: The single-beam data exported from CARIS HIPS and SIPS (x,y,z ASCII text file) were transformed in Esri ArcMap version 10.8.2.28388 to a point shapefile (.shp) utilizing the "Create Feature Class From XY Table" geoprocessing tool. The projection was set to WGS84 UTM 18N. The generated shapefile was visually scanned for any obvious outliers or problems. Next, a polyline shapefile (representing tracklines) was produced from the point shapefile using XTools Pro (version 22.0.4481) "Make Polylines from Points" geoprocessing tool for each survey platform (subFANs 22BIM03 and 22BIM05). Utilizing both the x,y,z (point) and trackline (polyline) shapefiles, a Python script was used to evaluate elevation differences at the intersection of crossing tracklines by calculating the elevation difference between points at each intersection using an inverse distance weighting equation with a search radius of 5 m. The root mean square (RMS) error for SLED (22BIM05), when crossing a trackline it previously surveyed, was 5.60 cm. The RMS error for WVR2 (22BIM03), when crossing a trackline it previously surveyed, was 4.65 cm. Once individual platform statistics were obtained, both datasets were merged into one file, and the crossing analysis yielded a 5.32 cm RMS error. These files were then exported from Esri ArcMap as x,y,z ASCII text (.txt) files using the XTools Pro "Table to Text" function. The resultant ASCII text file can be downloaded from this data release (Lyons and others, 2023) in Seven_Mile_Island_2022_SBES_WGS84_UTM18N_xyz.zip, and the trackline shapefile from Seven_Mile_Island_2022_SBES_WGS84_UTM18N_tracklines.zip. Person who carried out this activity:
   

   Erin O. Lyons

   Cherokee Nation System Solutions

   Biological Scientist Researcher V

   600 4th Street South

   St. Petersburg, FL
   

   USA

   727-502-8000 (voice)

   elyons@contractor.usgs.gov

   Data sources used in this process:

   • 22BIM03_SLED_SBES_WGS84_UTM18N_Level003_xyz.txt
   • 22BIM05_WVR2_SBES_WGS84_UTM18N_Level003_xyz.txt

   Data sources produced in this process:

   • Seven_Mile_Island_2022_SBES_WGS84_UTM18N_xyz.txt
   • Seven_Mile_Island_2022_SBES_WGS84_UTM18N_tracklines.shp

   Date: 2023 (process 6 of 6)

   Datum Transformation: NOAA/NGS's VDatum v.4.1 was used to transform the single-beam data points' horizontal and vertical datums (x,y,z). The first transformation was from WGS84 (G2139) UTM 18N into NAD83 (horizontal) UTM 18N and NAVD88 (vertical) using GEOID18. The second transformation was from WGS84 (G2139) UTM 18N into NAD83 UTM 18N and NAVD88 using GEOID12B. VDatum reports a nationwide standard deviation of 2.0 centimeters (cm) for ellipsoid - NAD83 transformations, and a nationwide standard deviation of 5.0 cm for NAD83 to NAVD88 transformations in the coastal regions of the continental U.S. For more information about the positional accuracy for these datum transformations, visit the Estimation of Vertical Uncertainties VDatum webpage, https://vdatum.noaa.gov/docs/est_uncertainties.html. The resultant ASCII text data files can be downloaded from this data release (Lyons and others, 2023) in Seven_Mile_Island_2022_SBES_NAD83_NAVD88_UTM18N_GEOID18_xyz.zip and Seven_Mile_Island_2022_SBES_NAD83_NAVD88_UTM18N_GEOID12B_xyz.zip. Person who carried out this activity:
   

   Erin O. Lyons

   Cherokee Nation System Solutions

   Biological Scientist Researcher V

   600 4th Street South

   St. Petersburg, FL
   

   USA

   727-502-8000 (voice)

   elyons@contractor.usgs.gov

   Data sources used in this process:

   • Seven_Mile_Island_2022_SBES_WGS84_UTM18N_xyz.txt

   Data sources produced in this process:

   • Seven_Mile_Island_2022_SBES_NAD83_NAVD88_UTM18N_GEOID18_xyz.txt
   • Seven_Mile_Island_2022_SBES_NAD83_NAVD88_UTM18N_GEOID12B_xyz.txt

3. What similar or related data should the user be aware of?
   Forde, Arnell S., DeWitt, Nancy T., Wei, Emily A., and Miselis, Jennifer L., 2023, Archive of Chirp Subbottom Profile Data Collected in 2022 From Seven Mile Island, New Jersey: U.S. Geological Survey data release doi:10.5066/P9PY4RR0, U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center, St. Petersburg, Florida.

   Online Links:

   • https://doi.org/10.5066/P9PY4RR0

How reliable are the data; what problems remain in the data set?

1. How well have the observations been checked?
   The accuracy of the data was determined during data collection. This dataset is derived from a single field survey using identical equipment set-ups, and staff; therefore, the dataset is internally consistent. Methods were employed to maintain data collection consistency aboard the platforms. During mobilization, each piece of equipment was isolated to obtain internal- and external-offset measurements with respect to the survey platform. All the critical measurements were recorded manually, and then digitally entered into their respective programs. Offsets between the single-beam transducers, motion reference units, and the antenna reference point (ARP) were measured using a geodimeter and accounted for during acquisition and (or) in post-processing. Differential Global Positioning System (DGPS) coordinates were obtained using the following post-processing software packages: NGS Online Positioning User Service (OPUS, https://geodesy.noaa.gov/OPUS/), and NovAtel’s Waypoint Product Group GrafNav, version 8.9). Due to an error in initial equipment set-up on the PWC, no data from the motion reference unit (heave, roll, pitch) were recorded for the first survey day 04-29-2022 (Day of Year [DOY]2022-119). This data was processed through the steps as normal, and thoroughly quality checked with the remainder of the survey data during the crossing evaluation. The crossing values were found to be acceptable and are included in this data release.
2. How accurate are the geographic locations?
   The NGS horizontal published numbers for Permanent Identifier (PID) JU0450, stamping STONE HARBOR 1932, was retrieved from the NGS datasheet database and converted from NAD83 (2011) into WGS84 (G2139) UTM 18N using the Horizontal Time-Dependent Positioning (HTDP) online transformation utility version 3.5.0 (https://www.ngs.noaa.gov/TOOLS/Htdp/Htdp.shtml). The latest realization G2139 was introduced on 01/23/21. The survey acquisition dates succeed this date; therefore, it was the appropriate datum realization for post-processing the navigation data which was acquired in the WGS84 datum. The resultant base position used for post-processing was 39°02’21.66695 North (WGS84-G2139), 74°46’08.81537 West (WGS84-G2139), and -34.526 meters (m) ellipsoid height (WGS84-G2139). The base station erected on PID DP1533, stamping 5 T 2 2013, served as the secondary base station, but it was not used for post-processing. The kinematic trajectories (rover to base) were processed using NovAtel’s Waypoint GrafNav software version 8.9.
3. How accurate are the heights or depths?
   The ellipsoid height value -34.526 m (WGS84-G2139) was used in NovAtel’s Waypoint GrafNav software. Please refer to the Horizontal_Positional_Accuracy_Report segment for vertical position transformation into ellipsoid height.
4. Where are the gaps in the data? What is missing?
   This data release contains single-beam bathymetry data points in the horizontal position and vertical elevation (x,y,z) from April/May 2022 collected off Seven Mile Island, New Jersey. Users are advised to read the complete metadata record carefully for additional details.
5. How consistent are the relationships among the observations, including topology?
   These data were collected during a single field activity with consistent instrument calibrations.

How can someone get a copy of the data set?

1. Who distributes the data set? (Distributor 1 of 1)
   
   Erin O. Lyons

   Cherokee Nation System Solutions

   Biological Scientist Researcher V

   600 4th Street South

   St. Petersburg, FL
   

   USA

   727-502-8000 (voice)

   elyons@contractor.usgs.gov
2. What's the catalog number I need to order this data set? Seven_Mile_Island_2022_SBES_NAD83_NAVD88_UTM18N_GEOID12B_xyz.txt, Seven_Mile_Island_2022_SBES_NAD83_NAVD88_UTM18N_GEOID18_xyz.txt, Seven_Mile_Island_2022_SBES_WGS84_UTM18N_tracklines.shp, Seven_Mile_Island_2022_SBES_WGS84_UTM18N_xyz.txt
3. What legal disclaimers am I supposed to read?
   This digital publication was prepared by an agency of the United States Government. Although these data were processed successfully on a computer system at the U.S. Geological Survey, no warranty expressed or implied is made regarding the display or utility of the data on any other system, nor shall the act of distribution imply any such warranty. The U.S. Geological Survey shall not be held liable for improper or incorrect use of the data described and (or) contained herein. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof.
4. How can I download or order the data?
   • Availability in digital form:

     Data format:

     comma-delimited text, shapefile Size: 110.1

     Network links:

     https://coastal.er.usgs.gov/data-release/doi-P9P07T3W/data/Seven_Mile_Island_2022_SBES_WGS84_UTM18N_xyz.zip https://coastal.er.usgs.gov/data-release/doi-P9P07T3W/data/Seven_Mile_Island_2022_SBES_WGS84_UTM18N_tracklines.zip https://coastal.er.usgs.gov/data-release/doi-P9P07T3W/data/Seven_Mile_Island_2022_SBES_NAD83_NAVD88_UTM18N_GEOID18_xyz.zip https://coastal.er.usgs.gov/data-release/doi-P9P07T3W/data/Seven_Mile_Island_2022_SBES_NAD83_NAVD88_GEOID12B_UTM18N_xyz.zip

   • Cost to order the data: None

Who wrote the metadata?

Dates:

Last modified: 23-Oct-2023

Metadata author:

Erin O. Lyons

Cherokee Nation System Solutions

Biological Scientist Researcher V

600 4th Street South

St. Petersburg, FL

USA

727-502-8000 (voice)

elyons@contractor.usgs.gov

Metadata standard:

Content Standard for Digital Geospatial Metadata (FGDC-STD-001-1998)